Gov. Dave Heineman of Nebraska approved a revised route for the Keystone XL pipeline through Nebraska on Tuesday, brushing aside vocal opposition from some citizen groups and putting final approval of the pipeline project squarely in the hands of the Obama administration.

The decision came a day after President Obama made an assertive pledge in his inaugural address to tackle climate change in his second term. Opponents of the pipeline, which would bring heavy crude oil from tar sands formations in Alberta, Canada, to refineries on the Gulf Coast, say that its extraction and consumption will significantly worsen global warming and that Mr. Obama's decision will be a test of his intentions.

Governor Heineman, a Republican, said in a letter to Mr. Obama and Secretary of State Hillary Rodham Clinton that his state's review found that the new route avoided sensitive lands and aquifers. Mr. Obama had rejected the previous route last January on the grounds that construction of the pipeline threatened Nebraska's Sand Hills region and that a spill could contaminate the critical Ogallala Aquifer.

Mr. Heineman said that the pipeline's operator, TransCanada, had assured him and state environmental officials that the chances of a spill would be minimized and that the company would assume all responsibility for a cleanup in case of an accident.

The State Department, which must review the 1,700-mile pipeline because it crosses an international border, is in the final stages of preparing an environmental-impact statement on the project. An earlier version found that the project would have minimal adverse effects along its route.

The American Petroleum Institute, a strong advocate of the project, applauded Nebraska's action, saying that it removed a critical hurdle to completion of the pipeline.

"With the approval from Nebraska in hand, the president can be confident that the remaining environmental concerns have been addressed," said Marty Durbin, the oil lobby's executive vice president. "We hope President Obama will finally greenlight KXL as soon as possible and get more Americans back to work."

Jane Kleeb, director of Bold Nebraska, a citizens' advocacy group that is staunchly opposed to the pipeline, assailed Mr. Heineman's move. "On the one hand, it's shocking the governor would turn his back so clearly on the Ogallala Aquifer and property rights in our state," she said. "However, given what the president said yesterday about climate change, what's clear is that the governor has made a very big political decision."

Ms. Kleeb said that if the president was indeed serious about addressing climate change, he had no choice but to reject Keystone XL.

Last week, a coalition of environmental groups, including the Sierra Club and 350.org, called on President Obama to kill the project, saying it would bring a rapid expansion of tar sands mining and greatly contribute to greenhouse gas emissions.

"From our perspective, this has always been about the climate, and it has always been about the president," said Daniel Kessler, a spokesman for 350.org, said on Tuesday. "It's unfortunate that the governor decided to do what he did. But ultimately this will come down to President Obama."

Mr. Kessler said that the group was intent on holding Mr. Obama to his vow to address climate change in his inaugural speech. His group is planning a large rally in front of the White House on Feb. 17 to urge the president to reject the pipeline, he said.

"The Keystone XL pipeline isn't dead yet," 350.org and the Sierra Club said in a statement. "If President Obama is serious about tackling climate change, he needs to reject KXL once and for all. And we're not going away until that happens."